Increased inflammatory signature in myeloid cells of non-small cell lung cancer patients with high clonal hematopoiesis burden

Purpose Clonal hematopoiesis of indeterminate potential (CHIP) allows estimation of clonal dynamics and documentation of somatic mutations in the hematopoietic system. Recent studies utilizing large cohorts of the general population and patients have revealed significant associations of CHIP burden with age and disease status, including in cancer and chronic diseases. An increasing number of cancer patients are treated with immune checkpoint inhibitors (ICI), but the association of ICI response in non-small cell lung cancer (NSCLC) patients with CHIP burden remains to be determined. Experimental Design We collected blood samples from 100 metastatic NSCLC patients before and after ICI for high-depth sequencing of the CHIP panel and 63 samples for blood single-cell RNA-seq (scRNA-seq). Whole exome sequencing (WES) was performed in an independent replication cohort of 180 patients. Results The impact of CHIP status on the immunotherapy response was not significant. However, metastatic lung cancer patients showed higher CHIP prevalence (44/100 for patients vs 5/42 for controls; P = 0.01). In addition, lung squamous cell carcinoma patients showed increased burden of larger clones compared to lung adenocarcinoma patients (8/43 for LUSC vs 2/50 for LUAD; P = 0.04). Furthermore, single cell RNA-seq analysis of the matched patients showed significant enrichment of inflammatory pathways mediated by NF-ĸB in myeloid clusters of the severe CHIP group. Conclusions Our findings suggest minimal involvement of CHIP mutation and clonal dynamics during immunotherapy but a possible role of CHIP as an indicator of immunologic response in NSCLC patients. Statement of translational relevance This study, employing CHIP-targeted sequencing and blood scRNA-seq, delivers four main messages with clinical implication; ([1][1]) No significant effect of CHIP status on the treatment response to ICI, ([2][2]) Minimal involvement of ICI treatment in the CHIP clonal dynamics of NSCLC patients, ([3][3]) Bias of high-burden clonal hematopoiesis towards lung squamous carcinoma over adenocarcinoma, and ([4][4]) An the altered inflammatory signature in myeloid cells of NSCLC patients with high CHIP burden. Specifically, our scRNA-seq analysis revealed enhanced inflammatory signatures involving the NF-kB and AP-1 pathways in the myeloid cells of patients with a high-CHIP burden. These findings lead to more precise understanding of CHIP involvement during ICI treatment in NSCLC patients. ### Competing Interest Statement The authors have declared no competing interest. [1]: #ref-1 [2]: #ref-2 [3]: #ref-3 [4]: #ref-4